1. Field of the Invention
The present invention relates to an image collating apparatus and an image collating method or, in particular, to an image collating apparatus and an image collating method in which a transfer application form (hereinafter sometimes referred to as the application form) is read by an image reader and collated with a plurality of types of transfer application forms preregistered in a transfer organization.
2. Description of the Related Art
Conventionally, a transfer application form having three vouchers is used for payment of the municipal taxes and the public utilities charges such as city gas, water and electricity. The three vouchers are separable by perforation. For example, the left voucher is used as a receipt of the money paid by a person at the window of a bank or a post office, the middle voucher is held by a transfer organization (bank or post office) and the right voucher is sent to a payee organization.
The transfer application form submitted to the window of a bank, etc. is read by an image reader for discrimination of the type thereof. For this purpose, the transfer organization such as the bank has a data base in which various types of transfer application forms issued by the municipalities and public bodies are preregistered for collation with a particular transfer application form. If the type of a transfer application form is identified by the image reader or, for example, it is determined that the transfer application form is issued by City A for transfer of a tax, the definition information for recognizing the characters of City A is read from the data base. The portion describing the amount in the transfer application form of City A is recognized, displayed on a display unit and checked by the teller.
The image reader of the transfer application form recognition system for reading the transfer application form at the window of the bank or the like is not installed for the sole purpose of reading such an application form but for various purposes. Also, the image reader is mainly designed for reading vertically-long documents of A4 size.
The application forms, however, include larger ones that cannot be read by the image reader used for reading a vertically-long A4-sized application forms. The teller is required to take the trouble of bringing such a larger application form to an image reader for A3-sized application forms, and it is desired to improve the image reader to handle this problem.
The object of the present invention is to provide an image collating apparatus and an image collating method, in which an application form can be collated accurately either in the case where the application form is read by an image reader capable of reading only a part of the application form in a transfer organization having a data base with the image of the whole application form preregistered for collation, or in the case where the application form is read by an image reader capable of reading the whole of the application form in a transfer organization having a data base with the image of only a part of the application form preregistered for collation.
In order to achieve the objects described above, according to one aspect of the invention, there is provided an image collating apparatus for determining the type of a document in such a manner that the image of the particular document read by a plurality of image readers having different reading sizes connected to an image input unit of the apparatus is sequentially collated with a plurality of document images preregistered in a data base, the apparatus comprising a preregistered image reading circuit, a document size determination processing circuit, an image retrieval circuit, a feature extraction processing circuit, an image collation processing circuit and a document determination circuit. The preregistered image reading circuit sequentially reads the document images preregistered in the data base. The document size determination processing circuit determines the size of a document by detecting the ends of the document from the document image input from the image readers. The image retrieval circuit operates in such a manner that, in the case where the document size that has been read is smaller than the size of the preregistered image, the preregistered image that has been read is retrieved in accordance with the document size that has been read, while in the case where the document size that has been read is larger than the size of the preregistered image, on the other hand, the document image that has been read is retrieved from one direction in accordance with the size of the preregistered image, so that the size of the document image that has been read is set to the size of the preregistered image. The feature extraction processing circuit extracts the feature of the document from the document image of which the size is set to the size of the preregistered image by the image retrieval circuit. In the feature collation processing circuit, the feature of the document extracted is matched sequentially with the features of the preregistered images of which the size is set to the size of the document image by the image retrieval circuit. In the case where the feature of the document coincides with the feature of a preregistered image, the type of the document is determined from the particular preregistered image.
The apparatus can further comprise an image rotating circuit, wherein in the case where the feature of the document fails to coincide with the features of all the documents preregistered in and read from the data base, the preregistered image is sent to the image retrieval circuit after being rotated by a multiple of 90 degrees.
In order to achieve the object described above, according to another aspect of the invention, there is provided an image collating method for an image collating apparatus for determining the type of a document in such a manner that the image of the particular document read by a plurality of image readers having different reading sizes connected to an image input unit of the apparatus is sequentially collated with a plurality of document images preregistered in a data base, wherein the type of the document is determined in such a manner that the document images preregistered in the data base are sequentially read, the document size is determined by detecting the document ends from the document image input from the image readers, and in the case where the document size that has been read is smaller than the size of the preregistered image, the preregistered image that has been read is retrieved in accordance with the document size, while in the case where the document size that has been read is larger than the size of the preregistered image, the document image that has been read is retrieved from one direction in accordance with the size of the preregistered image, the feature of the document is extracted from the document image, the document feature extracted is sequentially matched with the features of the document images, and in the case where the features of the two images coincide with each other, the document type is determined from the particular preregistered image.
In the image collating apparatus and the image collating method according to this invention, a document is collated and the document type can be determined simply by preregistering the documents of predetermined image sizes in a data base, reading a part or the whole of the document by image readers of any size and comparing the feature of the document with that of the preregistered images.